This offspring of the thunderstorm is the number one natural hazard killer each year. Most flash flood deaths occur at night trapping people in automobiles. The two key ingredients that contribute to flash flooding are rainfall intensity and duration - the rate of the rainfall and how long the rain lasts. Other factors include topography, soil conditions, and ground cover.

Flash floods occur within minutes or hours of excessive rainfall. Most flash flooding is caused by slow moving thunderstorms or thunderstorms repeatedly moving over the same area.

Johnson County is prone to flash flooding along many creeks including Turkey Creek, Brush Creek, Kill Creek and Indian Creek. Resident should know the potential in their area for flooding or flash flooding. Even 6 inches of fast-moving floodwater can knock you off your feet, and a depth of two feet will float your car! Never try to walk, swim, or drive through floodwaters. If you live within a flood plain, contact your insurance agent and verify that you carry flood insurance on your property.


When you receive a flood warning and if advised to evacuate, do so immediately!

Move to a safe area before access is cut off by floodwater.

Continue monitoring Weather radio, television, or Emergency Alert System (EAS) for information.


Avoid areas subject to sudden flooding.

If you come upon a flowing steam where water is above your ankles, STOP! Turn around and go another way.

Do not attempt to drive over a flooded road. The depth of the water is not always obvious. The roadbed may be washed out under the water, and you could be stranded or trapped.

Children should NEVER play around high water, storm drains, viaduct, or creeks, etc.


If fresh food has come in contact with floodwaters, throw it out.

Boil drinking water at least 3-5 minutes then let cool before using. Wells should be pumped out and the water tested for purity before drinking. If in doubt, call your local health authority.

Electrical equipment should be checked and dried before being returned to service.

Use flashlights, not lanterns, torches, or matches to examine buildings. Flammables may be inside.

Report any broken utility lines to appropriate authorities.

Never go near a downed or fallen electric power line. Always assume it is energized. Touching it could be fatal.

If you see someone touching a downed power line, don't try to rescue them yourself. Call the proper authorities.

Never drive over downed power lines. If contact is made with an energized power line while you are in your vehicle, remain calm, and do not get out unless it is on fire, wait for help to arrive. If you must exit the vehicle because of fire or other safety reasons, do your best to jump completely clear making sure you do not touch the equipment and the ground at the same time. Land with both feet together and shuffle away in small steps to minimize the path of electric current to avoid electrical shock.